Evaluation of bacteriological contamination of gastrointestinal and pulmonary endoscopes after cleaning and disinfection procedures

The increasing number of endoscopic interventions as well as the risk of patient to patient transfer of microorganisms contributed to put maintenance procedures of endoscopic instruments forward. The authors evaluated the quality of the procedures applied in their hospital during 2 years.: a manuel and a automated disinfection with Olympus ETD. 14 bronchoscopes, 20 coloscopes and 22 gastroscopes were studied. The internal channels were sampled by injecting a mixture inhibiting of the glutaraldehyde effect containing also a surfactant. They were shown to be more contaminated than the other sampled sites (moving extremity part, valves). The operator channel was shown to be more often contaminated in case of coloscopes in comparison with the results for the gastroscopes and bronchoscopes; however the contamination was lower after an automated maintenance instead of a manual maintenance (p = 0.05). Concerning storage, a period superior to 12 hours was shown to increase the level of contamination of the operator channel, and it was all the more contaminated since the drying was not well performed.